1. Field of the Invention
The present invention relates generally to air-dryable resins and processes for preparing air-dryable resins. More particularly, the invention relates to air-dryable intaglio ink resins that are dispersible in alkaline water, and processes for preparing same.
2. Description of the Related Art
Air-dryable alkyd resins, e.g., based on trimethylol propane, isophthalic acid, linseed oil fatty acids, and trimellitic anhydride, have been used in intaglio inks. These resins require the use of volatile solvents in order to be diluted to a low enough viscosity to be washed off a printing press with a cleaning solution.
Recently, pollution regulations and environmental concern have created a need for air-dryable resins that require minimum amounts of volatile solvents in order to be diluted to a viscosity low enough to make the ink containing the resin wash off the printing press. Such air-dryable resins must be suitable for printing, e.g., exhibit acceptable rheological properties such as viscosity and flow. Also, the resulting air-dried films must be resistant to chemical and physical attack.